Packing case



March 30, 1954 W. B. MORTON PACKING CASE Filed Aug. 17, 1949 INVENTOR.

ATTORNEYS.

Patented Mar. 30, 1954 PACKING CASE Woolridge B. Morton, New York, N. Y., assignor to Wilbro Corporation, New York, N. Y., a corporation of New York Application August 17, 1949, Serial No. 110,746

3 Claims. 1

This invention relates to improved packing cases of th type almost universally employed at the present time for shipping canned goods, soap, packaged goods and the like, and has for its object to provide a case of this kind which is reiniorced in a manner to make it suitable for goods of certain types for which the conventional packing case cannot now be used.

The conventional packing case or carton upon which my invention is an improvement is made of double-faced corrugated board or fiber board and consists of four vertical side walls and end flaps integral with the side Walls which are folded in overlapped relation and fastened together by gluing or stapling to form the top and bottom ends of the case. The board of which such case is made has ample tear resistance and tensile strength to adequately carry relatively heavy loads such as canned goods, sugar packages and the like, but the case, when fabricated in the conventional manner above described, does not in itself have sufficient stiffness to resist a heavy stacking load, particularly When the cases are stored in a humid atmosphere such as a ships hold or warehouse which is not suitably ventilated and air-conditioned. For such articles as cans, bottles, and the like, which are not injured by compression, this type of case has proved entirely satisfactory, but for fragile materials, even though of lighter weight, such as lamp bulbs, eggs, and fruit, where the goods are injured or destroyed when subjected to substantial pressures, the conventional corrugated paper case is not satisfactory, and wooden boxes are still employed for packing and shipping such articles.

According to my invention I reinforce the conventional packing case so that it will withstand the so-called stacking load to which it is subjected in storing and shipping to thereby make it suitable for shipment of perishable and fragile articles such as above mentioned.

My improved reinforced case is not modified in size or design so as to in any way interfere with its being handled with the packing and sealing machinerysuch as now universally employed where cases of this kind are used.

In the accompanying drawings I have illustrated a preferred embodiment of my invention and have also illustrated the various steps in the methods followed in the manufacture of my improved cases.

In the said drawings:

Fig. l is a perspective view of the flat blank as cut and scored for making my improved carton;

Fig. 2 is a sectional view on an enlarged scale of the collapsed carton;

Fig. 3 is a perspective view of the erected carton, filled, closed and sealed for shipment; and

Fig. 4 is a diagrammatic view of an apparatus used in makin the carton.

The material used for the carton is preferably fiberboard instead of th ordinary corrugated board, although the latter may be used if desired. The carton blank is of the conventional form such as shown in Figs. 1 and 2, and has the conventional score lines at the corners between the side walls and also between the edges of the side walls and the end flaps. In addition to these score lines the blank is formed in the making with longitudinal score lines 25, 26 on each side of the corner scores between the side walls and parallel thereto. The score lines 25 and 28 extend acros the side walls and also across the contiguous end flaps, as shown. The score lines 25 for any two of the corners which will be diagonally opposite when th carton is squared up, have their convex sides on the same side as the convex side of the corner scoring, whereas the score line 28 for the other two corners have their convex sides on the sides opposite to the convex sides of the corner score. The corner portion and the side wall at each corner between the score lines 25 or 26, as the case may be, is impregnated with a water-impervious thermosetting resin in a quantity such that when a corner is pressed between heated dies to set the resin, the corner of the carton between the score lines will be shaped to a right angle and will also be stiffened and strengthened to an extent necessary to carry the desired stacking load.

The resin may be applied to the described areas at the corners of the blank while the blank is still flat. In this case a watersoluble resin will be used which will be retained in the fiber of the blank when the water dries. Also, the four corners of the flat blank may be shaped and set while the blank is still flat. I prefer, however, to shape the corners at the same time that the lip 27 of the blank is attached to the edge of the side wall at the other end of the blank to thereby form the conventional fiat, tubular, knocked down carton. To this end a machine may be provided such as shownin Fig. 4, having a horizontal rotatable shaft on the end of which is supported a drum having four projecting corner supports 28 provided with electrical or other suitable heating means for heating and setting the resin with which the corners are impregnated. Supported over the upper corner support 28 when it is in its uppermost position is a stapling head 29 such as customarily used for stapling the lip 21 of the blank to the adjacent side wall, while supported opposite two corner supports 28 when positioned so that they are in horizontal alignment are two right angle die members 30 which are also provided with suitable heating means.

In forming the carton, the blank with the areas between the added score lines impregnated with the resin, is folded around the four projecting members 28 and the lip 21 placed under the edge of the end flap at the opposite end of the blank which, when folded around the four forms 28 is brought into line with the apex of the support 28 which is in the uppermost position under the stapling head 29. The stapling head will then be operated to staple the lip 21 to the overlying side wall of the blank in the usual manner. At the same time the heated dies 39 are pressed against the impregnated corners of the blank at the two horizontal corners, setting the resin and forming rigid, water-impervious corners at each of these vertical corners of the carton blank. The form is then turned 90 degrees to bring the vertical corners to horizontal position, and the dies 30 operated again to set the resin in the remaining two corners of the blank.

The blank is now removed from the form and flattened to the form shown in Fig. 2. That is,

the corners between the fold lines 25 are at the ends of the folded blank, whereas the corners adjacent the fold lines 26 are at the middle of the blank. As shown in Fig. 1 the score lines 25 have their convex side on the same side of the blank as the original corner score line, and hence permit the flaps to be readily folded together along the edges of the reinforced areas. The score lines 26 which have their convex sides opposite the convex side of the original corner score lines permit the walls of the blank to fold out- .1

wardly at the edges of the reinforced portions, so that the blank may be flattened to the extent shown in Fig. 2.

As stated above, the score lines 25 and 26 are carried across the end flaps of the carton so that when the cartons collapse the portions of the end flaps which extend from the reinforced areas at each side of the corner may fold with respect to the balance of the flaps and thus remain coextensive with the reinforced corner portions. If desired the portions of the end flaps between the score lines 25 and 26 respectively, and the edges of the flaps may be impregnated at the same time as the corners are impregnated, and the supports 28 and the cooperating dies 30 may be extended in length so as to set the resin in the marginal edges of the flaps at the same time that the resin in the corner itself is set. By this means a stiff reinforcing member is provided along each corner edge of the carton when the carton is squared up and the flaps closed.

The above described carton may be made very cheaply, and if the carton is made of heavy fibreboard and impregnated with a good thermosetting resin, the carton will have a strength and rigidity comparable to the ordinary wooden case which is now used for fruit and the like.

It will be understood, of course, the apparatus herein disclosed, while satisfactory for manufacture on a small scale, is shown by way of illustration only and that automatic machinery may be readily devised for carrying out the steps of impregnating, folding and stapling the blank and 4 setting the plastic in the corner portions of the blank in proper sequence. For such automatic machinery, however,-a separate application will be filed.

It will also be understood that the invention may be variously modified without departing from the scope of the appended claims.

I claim:

1. A carton having corners at the connected walls of the carton, said corners and portions of the adjacent wall sections being of rigid angular cross-section and score lines adjacent the edges of said rigid angular sections to permit the wall of the carton to bend with respect to the angular portion when the carton is collapsed, the score lines at two diagonally opposite corners having their convex side on the same side of the sheet as the corner fold and the score lines adjacent the other two corners having their convex sides on the opposite side of the sheet said carton having end-forming flaps attached to the edges of the said walls with the score lines parallel with said rigid corner portions extending across said end flaps.

2. A carton having corners at the connected walls of the carton, the walls of the carton at the corner being impregnated with plastic molded and set into a substantially rigid portion of angular cross-section and score lines adjacent the edges of said rigid angular sections to permit the wall of the carton to bend with respect to the angular portion when the carton is collapsed, said carton having end-forming flaps attached to the edges of the said walls with the score lines parallel with said rigid corner portions extending across said end flaps.

3. A carton having corners at the connected walls of the carton, the walls of the carton at the corner being impregnated with plastic molded and set into a substantially rigid portion of angular cross-section and score lines adjacent the edges of said rigid angular sections to permit the wall of the carton to bend with respect to the angular portion when the carton is collapsed, said carton having end-forming flaps attached to the edges of the said walls with the score lines parallel with said rigid corner portions extending across said end flaps, the portion of said end flaps between said score lines and adjacent edges of the flaps being impregnated with plastic molded and set to stiffen such portions of the flaps.

WOOLRIDGE B. MORTON.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 937,443 Kelley Oct. 19, 1909 941,356 Byrne Nov. 30, 1909 1,218,872 Lafore Mar. 13, 1917 1,302,507 Cady May 6, 1919 1,425,914 Swift, Jr Aug. 15, 1922 1,433,281 Hubard Oct. 24, 1922 1,527,021 Wandel Feb. 17, 1925 1,785,391 Russell Dec. 16, 1930 1,806,863 Paisseau May 26, 1931 1,913,055 Keller June 6, 1933 2,240,256 Elmendorf Apr. 29, 1941 2,388,267 Junkin Nov. 6, 1945 2,392,734 Haberstump Jan. 8, 1946 2,442,651 Johnson June 1, 1948 

